Heater



FIG. 1 is a front perspective view of a heater, showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a left side elevational view thereof;

FIG. 7 is a right side elevational view thereof;

FIG. 8 is a front perspective view of a second embodiment of a heater;

FIG. 9 is a front elevational view thereof;

FIG. 10 is a top plan view thereof;

FIG. 11 is a bottom plan view thereof;

FIG. 12 is a rear elevational view thereof;

FIG. 13 is a left side elevational view thereof;

FIG. 14 is a right side elevational view thereof.

The ornamental design for a heater, as shown and described.